The story of Gideon Moor reveals previously unexplored instances of black activism dating back to pre-Revolutionary War Pennsylvania. Along with his wife, Jenny, and nine children, Moor was enslaved to George Michael Weiss, a German Reformed minister in the Upper Perkiomen Valley, and his wife, Anna. After the death of the Weisses, Moor launched a campaign for liberation for himself and his family members. Not content with freedom, Moor went to court to claim property rights, using the naturalization process to reinforce his claims. Moor partnered with Quaker antislavery activists in his struggles against injustice. His story deepens understandings of early antislavery organizing and networking. Experienced with the world of his contentious German Reformed neighbors and likely inspired by swelling revolutionary rhetoric, Moor alarmed his opponents as he left a record of initiative and persistence that adds important dimensions to the early history of the abolition movement.